NASA Satellite Laser Images Reveal Extreme Polar Melting

After analyzing 50 million laser measurements from a NASA satellite, British scientists at the British Antarctic Survey (BAS) have painted a frightening picture for Greenland and Antarctica, with glaciers melting at extreme rates. While the fact that polar ice is melting is not breaking news, the rate at which it is moving, and the method for gathering the technology is surprising. We have been following the news of the rapid ice melts at the poles all summer, and this new study confirms some serious fears.

The results of the study are published in Nature. "We were surprised to see such a strong pattern of thinning glaciers across such large areas of coastline," [Hamish] Pritchard of the British Antarctic Survey said in a statement according to CBS news. "It's widespread and in some cases thinning extends hundreds of kilometres inland."

The satellite laser by NASA is used by BAS scientists to measure the tiniest changes in the thickness of glaciers and ice sheets along the coast of the Amundsen Sea in West Antarctica, which is where polar ice is melting fastest. The laser images can acquire high-resolution data particularly where coastal areas are steep, which are areas where the radar altimeters used on other satellites can't make out important details that give scientists the most accurate measurements. They found that faster flowing glaciers are at the root of the rapid polar melting.

In May we noted that scientists don't think the West Arctic ice sheets will melt completely, but the loss of ice and the rise in sea level as a result are definitely of concern. Though that could change. And on the other pole, the scientists say that a full melt of the Greenland ice would push sea level up by about 7m (20ft).

According to the scientists, the speed at which some of the glaciers now move towards the sea is outpacing the rate at which ice can be restored to the land through normal precipitation patterns, as noted by BBC. A total of 111 fast-moving Greenland glaciers were studied and in comparison to the slow-moving ice beside them, 81 were shown to be thinning at twice the rate, thinning faster as they speed up. It is the speed at which the glaciers are moving that is causing the dramatic loss, and not simply faster melting from warmer temperatures.

The results of the satellite measurements are a key part of accurately predicting rises in sea level as the ice melts into the ocean, so we can better understand where - and more importantly, who - will be affected as ice literally slips into the sea.